Apparatus fox distilling substances



W. M. DUNCAN.

APPARATUS FOR DISTILLING SUBSTANCES.

APPLICATION FILED AUG.29,19I8.

Patented Feb. 2] 1922.

3 SHEETS-SHEET l.

W. M. DUNCAN.

APPARATUS FOR DISTILLING SUBSTANCES.

- APPLICATION FILED AUG.29, 19H1. 1,407,018, Patented Feb. 2l, 1922'.

3 SHEETS-SHEET 2.

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. W. M. DUNCAN.

APPARATUS FOR DISTILLING SUBSTANCES.

VACUUM PUMP 4- STEAM APPLICATION FILED AUG.29| 1918.

Patented Feb. `2l, 1922.

3 SHEETS-SHEET 3.

UNITE@ ,STATES WILLIAM Mv. DUNCAN,

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APPARATUS FOR DISTILLING SUBSTANCES.

essere.

Specification of Letters Patent.

Patented Feb. 21, 1922.

Application filed August 29, 1918; Serial No. 251,973.

To @ZZ whom it may concern: i

Beit known that I, IVILLIAM M. Dune-m, a citizen of the United States of America, a resident of Alton, in the county of Madison, State of Illinois, have invented certain new and useful Improvements in irpparatus for Distilling Substances, of whichthe following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification. A

My invention relates to improvements in apparatus for distilling solid substances such as coal, shale, wood, etc.

The lobjects of the invention are to increase the yield of liquid product-s, to economize in the use of fuel. to save labor in the operation of the retort, to provide an improved fractional Vdistillation means, and to enable the distillation to be carried out continuously for an indefinite period of time.

In the preferred form of the invention, diiferent portions of the retort are maintained at diderent temperatures to provide low, intermediate and high temperature zones for the vaporization of the different fractions to be obtained from the charge of solid material. The charge is preferably delivered from a source of supply to an endless conveyor whereby the fresh charge is caused to travel continually from the low temperature zone, through the intermediate zone and thence through the zone of highest temperature, the residual product being continually discharged from the last mentioned zene. By continually admitting fresh charge and continually discharging the residual produc-ts while the substance to be distilled is traveling through-the retort, I enable the operations to be carried out continually. Furthermore, the traveling charge can be handled mechanically with very little labor and attention on the part of the operator. i

An important feature of the invention lies inthe peculiar manner in which the different fractions are taken from the charge and sep-v arated from eachother in the retort. As the traveling charge advancesthrough the low, intermediate yand high temperature vlzones,

` the various fractions are permitted to escape freely in the form-of vapor, each product being quickly removed from the zone in whichit isvaporized, and this is accomplished without passing the vapor from one zoneto another and without subjecting any of the fractions to a temperature higher than is necessary to free it from the charge. The most volatile and most valuable products are not injured or converted into fixed gases by subjection to high temperatures. Thev are quickly taken from the traveling charge in the low temperature zone. This increases the yield of the most valuable liquid prod ucts.

In addition to avoiding the production of -alarge percentage of gas and increasing the yield of more valuable liquid, the present invention avoids heat losses which would b e incurred by subjecting the volatile yfractions to unnecessary and undesirable high temperatures--- Furthermore, since the dit'- ferent vaporized fractions are not overheated in the retort they can be more easilv andmoie economically condensed'. f u

Fig. I is a diagrammatical plan view of an apparatus embodyingl the features of my invention. Fig. II is a longitudinal section, partly in elevation, illustrating the retort. Y

.'Fig. III is a diagraniinatical view of the apparatus, the retort being shown in section. To illustrate the invent-ion I have shown a retort provided with an elongated airtight vaporizing chamber A containing an endless traveling conveyor 1 whereby the charge is transmitted through the retort. The conveyor I preferably consists of a number of endless chains (Figs. II and III) mounted on wheels 2 and 3, the latter being fixed to a power shaft 4 which may be rotated by any suitable mechanism to cause the conveyor to travel at any desired speed. 5 designates an intake receptacle in the forni of a hopper located at one end of the airtight v'aporizing chamber, and 6 is a tubular outlet member for the discharge of residual products from the retort. The outlety meinbei 6 extends downwardly from the va orizing chamber, and its lower end extends into a body of water in a residuum receptacle 7,k

thereby forming a water seal to prevent-the admission of air to the vaporizing chamber. 8 designates-a conveyor arranged in the receptac e 7 to remove the coke or other residual products from the water. To provide for the discharge of fine articles of solid matter which drop through the endless chain conveyor l, a tubular outlet member 9 extends downwardly froin the intake end of the airtight vaporizing chamber, and the lower end of this outlet member extends into a body of water in a receptacle 10, so as to form a waterseall The endless chain conveyor 1 and the elongated air-tight vaporizing chamber A are preferably arranged horizontally and the intake receptacle 5 extends upwardly from one end of said Chamber A, While the outlet member 6 extends downwardly from the opposite end. The lower end of the intake receptacle 5 is open, as shown in Fig. II, to provide for the admission of the fresh charge to the traveling conveyor 1.

The retort herein shown is provided with a furnace B and lues 12 and 13 whereby hot gases and other products of combustion are conducted from the furnace. The flue 12 lies directly above the air-tight vaporizing chamber A, and it constitutes a heating chamber for the transmission of heat to the travelin charge supported on the conveyor 1. To eectively utilize the heating medium, the flue 12 may be provided with baiiles 14, staggered as shown in Fig. I to deflect and retard the hot gaseous fluid passing from the furnace. A heat radiating member 15 forms the bottom wall of the flue 12, and also forms the top wall of the air-tight vaporizingchamber A, the heat being trans mitted from the lue12 to the member 15 from which it is radiated to the traveling charge on the conveyor 1. The charge is thus heated and vaporized without being ignited, and without coming into direct contact with the products of combustion passing from the furnace. Itis important to note that the heating fluid passing through the flue 12, travels in a general direction opposite to the direction of travel of the charge on the conveyor 1. By transmittingthe charge and the heating medium in opposite directions, as shown in Fig. II, I subject the outgoing portion of the charge to a very high temperature, while the incoming portion of the charge is maintained at a'relatively low temperature. The

outlet end of the vaporizing chamber is adjacent Vto the incoming heating medium which passes into the llue 12 at a very high temperature, and the intake end of the va porizing chamber is subjected to the relatively lowdegree of heat transmitted from the heating medium at the discharge end of the flue 12. This is a simple and convenient manner of establishing and maintaining different temperature zones in the vaporizing chamber. In the destructive distillation of coal, the low temperature zone at the intake'end of the vaporizing chamber is preferabl maintained at a temperature of about 300o if., while the high temperature zone at the exit end of said chamber is preferably maintained at about 1000o F., the intermediate zones being maintained at intermediate temperatures ranging between 300 F. and 1000or F.

' vacuum The charge passing from the bottom of the intake receptacle 5 is admitted to the low temperature zone where the temperature is high enough to vaporize the most volatile fractions, and as the charge travels slowly through the intermediate and high temperature zones it is subjected to gradually increasing temperatures so as to vaporize the intermediate and high boiling point fractions. To economize in the use of fuel; to avoid the production of a large percentage of permanent gas; to facilitate the condensation of the products, and to increase the yield of liquid products, I prevent the vapors from being overheated in the retort, and this is preferably accomplished by quickly removing the vapors as soon as they are evolved in the vaporizing chamber. The vapors are not permitted to pass from one zone to another and they are not conducted along any of the relatively hot portions of the retort.

16 designates va or conductors extending entirely across t e air-tight vaporizing chamber A and surrounded by the endless conveyor l, said vapor conductors being open at the top lto receive the vapors passing from the traveling charge. The charge-supporting portion of the conveyor rests upon the upper edges of the vapor conductors. It will be noted that the traveling charge is interposed between and in contact with the conveyor and the heat radiating wall 15, while the charge-supporting portion of the conveyor is likewise interposed between and in contact with the charge and the vapor conductors 16.

Vapor pipes 17 lead from the vapor conductors 16 to fractional condensers 18, and each condenser is provided with an outlet pipe 19 (Fig. III) leading to a receiving tank 20. Each receiving tank 20 is preferably connected by means of a pipe 21 to a ump 22, as shown diagrammatically in ig. III. This pump may be operated to create an induced draft in the vapor line so as to quickly and positively remove the vapors from the charge, but it is to be understood that the invention is not limited to a draft producing means of this kind, and if desired, the pressure in the vaporizing chamber may be utilized to eX- pel the vapors which are free to escape from the different zones.

It will now be readily understood, that a charge of solid substances, such as coal or shale is maintained in the intake receptacle 5 from which it is discharged to the endless chain conveyor 1, the latter being driven continually so as to continually advance the charge from one zone to another, thereby graduallyincreasing the temperature of the traveling charge. As soon as they are converted into vapor, the different fractions are drawn downwardly from the zone in which they are vaporized, the vapors being conducted between the -links of the chain conveyor 1 and into the vapor conductors 16. The different vaporized fractions are not permitted to commingle with each other in the retort, and after being positively separated by passing into the vapor conductors 16, they are delivered to lthe separate fracf tional condensers 18 from which the several liquid products are recovered. Some gas will of course be formed, but the production will be reduced to a minimum for the reason that the vapors are not overheated, and this results in a number of other important advantages which will be readily understood by those skilled in the art.

To carry out the operation continuously, the vapor conductors 16 should be cleaned occasionallyk to remove the fine particles of solid substances which drop through the endless chain conveyor, and this should be done without admitting air to the vaporizing chamber. One end of each vapor conductor 16, is, therefore, provided with a discharge pipe 23 which extends downwardly and into a body of water in a receptacle 24, and each vapor pipe is provided with a steam pipe 25 having a valve 26 and a `discharge nozzle 25 (F ig. III) the latter being adjacent to one end of a vapor conductor 16. Whenever it is necessary to clean the vapor conductors 16, steam is admitted through the steam pipes 25 to create steam blasts whereby the particles of solid matter are projected from said conductors 16 and discharged through the pipes 23 to the water in the receptacle 24. This water seals the lower ends of pipes 23 to exclude air from the vaporizing chamber. All of the outlets of the vaporizing chamber are sealed, and this chamber is not in communication with the furnace or lues from which the heat is transmitted to the traveling charge.

The charge contained in the intake hopper' 5 can usuallybe relied upon to prevent the admission of air through the charge inlet, and I, therefore, do not deem it necessary to show any other means for excluding air at this point.

I claim 1. In an apparatus for distilling solid substances, a retort provided with a vaporizing chamber having an inlet for the admission of the charge and an outlet for the discharge of residual products, an endless traveling conveyor whereby the charge is supported and advanced from said inlet to said outlet, a heat-transmitting member located directly above the charge-supporting portion of said conveyor, vapor-conducting means including a vapor intake member surrounded by said endless traveling conveyor and extending from the bottom of said charge-supporting portion, the top of said vapor intake member being open at the bottom face of said charge-supporting portion to receive the vapor passing downwardly therefrom,` and means for condensing thevapor. v

2. In an apparatus for distilling solid substances, a retort provided with a vaporizing chamber having an inlet for the admission of the charge and an outlet for thedischarge of residual products, an endless traveling conveyor whereby the charge is supported and advanced from said inlet to said outlet, aheat-transmitting member located directly above` the charge-supporting portion of said conveyor, vapor conductors leading from said vaporizing chamber, each of said vapor conductors including an intake member surrounded by said endless traveling conveyor and extending across the bottom face of said charge-supporting portion, the top of each intake member being open at the bottom of said charge-supporting portion, and means for condensing the vapors passing from'said vapor conductors.

3. In an apparatus fordistilling solid substances, a retort provided with a vaporizing chamber, heating means whereby high and low temperature zones are maintained in said vaporizing chamber, means for advancing the charge in said chamber from the low temperature zone to the high temperature zone, the last mentioned means including an endless conveyor located in said retort, separate vapor conductors leading from the high and low temperature zones, each of said vapor .conductors including a vapor intake member surrounded by said endless conveyor and open adjacent to the charge, so as to receive vapor at the point where it escapes from the charge, and means for condensing the different vapors passing from the high and low temperature zones.

4. In an apparatus for distilling solid substances, a retort provided with an air-tight vaporizing chamber having an intake for the admission of the charge and a discharge opening for the discharge of residual products, heating means whereby high, low and intermediate temperature zones are maintained in said air-tight vaporizing chamber, the low temperature zone being maintained adjacent to said intake and the high temperature zone being adjacent to said discharge opening, means whereby the charge is gradually advanced in said vaporizing chamber from the lou7 temperature zone, through the intermediate zone, and thence through the high temperature zone, said feeding means including a traveling conveyor arranged in said air-tight vaporizing chamber, non-intercommunicating vapor conductors whereby the diferent vaporized fractions are separately conducted from the different zones, each of said vapor conductors having an intake opening at the chargesupporting portion of said traveling conveyor, said charge-supporting portion of the conveyor being interposed directly between said vaporizing chamber, means for advancing the charge in said chamber trom the low ltemperature zone to kthe high temperature Zone, the last mentioned means including anv endless conveyorlocated in said retort, separate vapor conductors leading from the high and low temperature zones, each of said vaporiconductors including a vapor intake member surrounded by said endless conveyor and open adjacent to the charge, so as to` receive vapor at the point where it escapesfrom the charge, means for condensing the vdifferent vapors passing from the high .and low temperature zones, and suction devices whereby the vapors are drawn from said charge-feeding portion and into the open intake members adjacent thereto. 6. In an apparatus for distilling solid substances, a retort provided With a vaporizing chamber having an inlet for the admission of the charge and an outlet for the discharge of residual products, an endless travelingconveyor whereby the charge isv advanced from said inlet to said outlet, heating means whereby progressively varying temperature zones are maintained in said retort, a plurality of non-intercommunicating vapor conductors, each having an intake substantially eoextensive with the width of said Vaporizing chamber, each yof said intakes being open immediately adjacent the charge, whereby each of said conductors is placed in corniinunication with only one of said temperature zones. j

7. In an apparatus for distilling solid substances, a retort provided with a vaporizing chamber having an inlet for the admission of t-he charge and an outlet for the disch-argent residual products, an endless traveling conveyor whereby -the charge is advanced from said inlet to said outlet, heating means whereby progressively varying temperature zones are maintained in said retort, said heating means including a flue having a heat-radiating Wall exposed to the charge and a series of baille Walls whereby the heating medium is .retarded and deflected in a. tortuous course on said heat-- radiating wall, a plurality of Ynon-intercommunicatingl vapor conductors each having an intake substantially coextensive with the width of said vaporizing chamber, each of said intakes being open immediately adjacent the charge, whereby each of said conductors is placed in communication with only one of said temperature zones.

In testimony that I claim the foregoing I hereunto aix my signature.

VILLIAM M. DUNCAN 

